My dad got me this derby muscle bike for me for my birthday. The guy he got it off of didn't know anything about it and I can't find anything on the Internet about this bike. I don't even know the name of the bike. All I do know is that the head badge says Derby W. Germany. The chain guard also says derby on it. I'm asking for help on what the bike is called, what year it is from and anything else you great people can tell me about my bike. Please and thank you!